Micrometer-calipers.



R. C. KEPPIB.

MICROMETBR GALIPBRS.

APPLIOATION FILED APR. 1911.

1,006,660. Patented oct. 24,1911.

AT T DRNEY COLUMBIA PLANOGRAPH c0..wASHINGTuxx R. C. KBPPIL MIcRoMBTBR GALIPERS.

APPLIOATION FILED APB` B, 1911. 1,006,660, Patented Oct. 24, 1911;

2 MEETS-SHEET 2.

ATTDFQNEY COLUMBIA PLANOGRAIH (30.,WASHINUTON, D, C.

UNiTED sTATEs PATENT OFFICE.

RANDOLPH C. KEPPIE, OF PROVIDENCE, RHODE ISLAND'.

MICROMETER-CALIPERS. f if To all whom it may concern:

Be it known that I, RANDOLPH C. Knrrin, a citizen of the United -States, residing at Providence, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Microineter-Calipers, of which the following is a specification.

My invention relates to calipers or dividers and has for its essential objects the combination of the functions of locating the center and ascertaining the outside measurements of objects; a capacity for indicating in a single device not only inicrometric measurements but those of greater magnitude; in providing a maximum range of movement of the legs and speed in moving the same.

A further object is to provide means for centering the pointer.

Other objects and advantages will b'e hereinafter pointed out and made the subject of claim.

To the enumerated and suggested ends my invention consists in such novelv parts and combinations of parts as fall within the scope of the appended claims.

In the accompanying drawings which form a part of this specification and in which like reference characters indicate like parts throughout the views, Figures 1 and 2 are `front and side elevations respectively of a pair of calipers embodying my invention and in closed position, Fig. 3 a front elevation of the same in distended or open position, Fig. 4 a top plan view of the carriage or movable member with its top or housing partially broken away, and showing parts in horizontal section, Fig. 5, a central longitudinal sect-ion of the same on line ai of Fig. 4and Fig. 6, a section on line y y of Fig. 1.

My novel instrument in its present and approved embodiment comprises legs 1 of similar shape and dimensions, provided with rearwardly directed upper end portions 3 upon whose ends are attached by screws 5 or otherwise arms or links 7 whose ends overlap and have longitudinal slots 8 to receive a bolt 9 upon which is a nut 10. The screw and slot connection described has advantages for adjustment, but any other preferred pivotal connection may be employed for connecting the contacting ends of the links 7. The vertical portion of each arm from Specification of Letters Patent.

Patented Oct. 24, 1911.

Application led April 8, 1911.. Serial No. 619,800.

its top nearly to its bottom is provided with screw threads 12 and curves inwardly from its top extremity, then outwardly, and then inwardly, as at 14, 15, and 16, respectively, forming reverse bends of which the lower has the most pronounced curvature. In the center of the contacting faces each arm at its lower extremity is a semicircular cavity 18. Fixed to or integral with one of the legs is a lateral frame comprising a flat Ibar 20 curved to conform to the curve' of the adjacent portion of the leg, and integral arms or supporting portions 21 and 22 extending from the bar to the top and to an intermediate portion respectively of the leg. The bar20 is provided with graduations 24 preferably of inches and the greater subdivisions of inches for measurements of greater extent than the capacity of the micromet-ric graduated device.

A shallow oblong carriagejor casing 26 has upwardly inclined end portions 27 and 28. The casing comprises a top plate 30, a bottom plate 3l, and a side wall 32. The top and bottom plates of the portion 27 are provided with openings 33 and 34 respectively to allow passage therethrough of one of the legs. The corresponding platesl of the end 28 have openings 35 and 36 respectively through which passes the other leg, upon which is mounted a bevel gear 38 provided with a thread 39 engaging the thread of the leg. This gear meshes with a bevel gear 42 loose on a vertical tube 43 integral with or fixed in the center of the casing portion 26 and extending above and below the saine, which gear in turn meshes with a third bevel gear 45 provided with an interior thread 46 engaging the thread of the other leg. The upper end faces of the three gears bear against the top plate. The lower portion of the gear 45 is journaled in the openings 34. One end of the gear 38 is extended to form a hub or tube portion 48 frictionally fixed to which or integral with which is an external sleeve 49 carrying a milled head 50. The sleeve 49 has a bearing in the bottom plate and is provided upon its exterior face with a scale of graduations of thousandtlis of an inch 51, which coperates with a zero line 52 on the casing. Upon the end of the casing portion 27 are interspaced pointers or lugs 53 which slidably engage opposite sides of the bar 20.

Movably mounted in the tube 43 whose projecting lower portion is split as at 44, is a pointer or pencil 55 whose point 56 is in vertical alinement with the cavities 28 when the legs are in closed position.

To open the calipers the milled head is manually turned rotating the gear 38 which in turn rotates the gear 45 through the gear 42, thus through t-he threaded connections of the two gears with the legs moving the carriage upwardly in a horizont-al position and gradually expanding the legs. It will be noted that as the gears approach the upper ends of the arms as at 14 the curves of the latter are such as to separate the lower portions of the arms at an increasing ratio, thus affording quick and unusually extended distension.

The pointer is adapted to locate th center of an article embraced by the legs, and when it is desired to countersinlr with the pointer the oset character of the portions 3 of the legs make the upper end of the pointer 55 accessible to a hammer. When the pointer has a lead point that requires sharpening the cavities 18 in the arms are serviceable for proving the accuracy of the new point. Larger measurements may be read upon the scale 24, and minute measurements may be taken on the scale 51.

What I claim is,-

1. In a pair of calipers, legs movable toward and away from each other and provided with threads, a carriage provided with openings through which the legs pass, gears in the carriage provided with threads engaging the threads'of the legs, and means for transmitting motion from one gear to the other.

2. In a pair of calipers, legs movable toward and away from each other and provided with threads, a carriage provided with openings through which the legs pass, gears in the carriage provided with threads engaging the threads of the legs, and an intermediate gear connect-ing the first mentioned O'ears.

D 3. In a pair of calipers, legs movable toward and away from each other and provided with threads, a carriage provided with openings through which the legs pass, gears in the carriage provided with threads engaging the threads of the legs, operative connections between the gears, and an operating nut fixed to one of the gears.

4. In a pair of calipers, legs pivotally connected with each other at one end and movable toward and away from each other, a carriage movable longitudinally of the legs, and rotary means in the carriage enf gaging t-he legs for imparting longitudinal movement to the carriage.

5. In a pair of calipers, legs pivotally connected with each other at one end and movable toward and away from each other, a carriage provided with openings through which the legs pass, means in the carriage engaging the legs for moving the carriage longitudinally of the legs, and a pointer disposed in the plane of the legs mounted in the carriage equidistant each leg.

6. In a pair of calipers, legs movable toward and away from each other, a carriage provided with openings through which the legs pass, means in the carriage engaging the legs for moving the carriage longitudinally of the legs, a split tube iXed in the carriage equidistant the legs, and a pointer slidably mounted in the tube.

7 In a pair of calipers, legs provided with rearwiardly extending end portions, links connected at one end to said portions and provided at their other end with oblong slots, pivotal means in the slots connecting -the links, a carriage provided with openings through which the legs pass, means in the carriage engaging the legs for moving the carriage longitudinally of the legs, a pointer slidably mounted in the carriage in the vertical plane of the legs and equidistant each leg.

8. In a pair of calipers, the combination of two curved legs provided with threads upon their curved port-ions, means for pivotally connecting the ends of the legs, a carri age provided with openings through which the legs pass, gears in the carriage provided with threads, engaging the threads of the legs, operative connections between the gears, and an operating nut fixed to one of the gears.

9. In a pair of calipers, the combination of two legs curved oppositely to each other, one of said legs being provided with a thread upon its curved portion, a carriage provided with openings through which the legs pass, a gear in the carriage provided with a thread engaging the thread on the leg, and an operating nut Xed to the gear.

10. In a pair of calipers, the combination ot' two legs curved oppositely to each other, one of said legs being provided with a thread upon its curved portion, a carriage provided with openings through which the legs pass and provided with a zero line, a gear in the carriage provided with a thread engaging the thread on the leg, an operating nut iixed to the gear, and provided with graduations registering with the zero line.

11. In a pair of calipers, the combination of two legs provided with threads, a bar mounted upon one leg parallel therewith and provided with graduations, a carriage provided with openings through which the legs pass, lugs upon one end of the carriage slidably engaging the bar, gears in the carriage provided with threads engaging the threads of the legs, operative connections between the gears, and an operating nut fixed to one of the gears.

12. In a pair of calipers, the combinati@- of two curved legs provided with threads first mentioned gears, and an operating nut 10 upon their curved portions, pivotal eonnee- Xed to one of the bevel gears.

tions bet-Ween the ends of the legs, a carriage In testimony whereof I have affixed my providd with inclined end portions, said signature in presence of tWo Witnesses.

incline portions being provided with openings through Which the legs pass, bevel gears RANDOLPH C' KEPPIE in the carriage provided With threads engaging the threads of the legs, a third gear mounted in the carriage meshing with4 the Witnesses:

HoRATIo E. BELLows, GEORGE H. MoLAUGHLiN.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C. 

